Synthesis and characterization of aromatic polyamides containing pendant naphthalene-8-oxybenzamide units

Autor: N. N. Maldar, Arati V. Diwate, Mahesh B. Gurame, V. P. Ubale, Makarand D. Joshi, Shivaji. D. Ghodke, Aslam B. Tamboli
Rok vydání: 2021
Předmět:
Zdroj: Journal of Polymer Research. 28
ISSN: 1572-8935
1022-9760
DOI: 10.1007/s10965-021-02705-9
Popis: The new aromatic m-catenated diamine, N-(3, 5-diaminophenyl)-4-(naphthalen-8-yloxy)benzamide was synthesized from 1- naphthol and 4- fluoro benzonitrile. A series of novel aromatic polyamides; containing pendant bulky naphthalene-8-oxybenzamide unit; was synthesized from the diamine and several structurally different aromatic diacids such as 4,4’-Oxydibenzoic acid, Naphthalene-2, 6-dicarboxylic acid, 4,4’-Sulfonyldibenzoic acid, Biphenyl-4,4’-dicarboxylic acid, and 4,4’-(perfluoropropane-2, 2-diyl) dibenzoic acid via direct Yamazaki’s phosphorylative polycondensation method using triphenyl phosphite (TPP) as a condensing agent in pyridine (Py)/LiCl/1-methyl-2-pyrrolidone (NMP) solvent system. These new kink structured polyamides were characterized by inherent viscosities, solubility in organic solvents, FT-IR, DSC, TGA and XRD techniques. The polyamides were obtained in good yields and had inherent viscosities in range 0.35 and 0.55 dL/g. These polyamides showed good solubility in amide type polar aprotic solvents namely N, N’ dimethyl formamide (DMF), 1-methyl-2-pyrrolidone (NMP), N, N’ dimethyl acetamide (DMAc), dimethyl sulfoxide (DMSO) and partly soluble in m-cresol, tetrahydrofuron (THF). Polyamides showed glass-transition temperatures in the range 207 °C-245 °C indicating their processability at these temperatures. The 10% weight loss temperatures as determined by the thermogravimetric analysis were more than 413 °C, indicating a good thermal stability. X-ray diffraction patterns of these polyamides indicated the amorphous nature, which is reflected in solubility behavior.
Databáze: OpenAIRE
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